Fluid delivery systems are commonly used today in a wide variety of applications. Air delivery systems such as forced air systems are commonly used to deliver conditioned air to one or more locations within a house or building. Water delivery systems such as sprinkler systems are commonly used for delivering water to sprinkler heads in, for example, a buried sprinkler system or in a fire prevention sprinkler system. Water circulation systems are commonly used to heat and/or cool both residential and commercial buildings. These are just a few examples of fluid delivery systems.
Fluid delivery systems often include a network of pipes or ducts. In many cases, one or more valves or dampers, such as zone valves or dampers, are used to control the fluid flow through all or part of the pipes or ducts of the distribution network. In some cases, the network of pipes or ducts is broken up into zones, where some or all of the zones can be independently activated by one or more corresponding zone valves or dampers.
In a fluid delivery system such as described herein, the amount of fluid available to a particular zone can vary depending on how many other zone valves or dampers are open or closed. In a water delivery system such as an underground sprinkler system, the amount of water pressure available to a specific sprinkler head will depend on a gross water pressure available to the system itself as well as the number of open sprinkler heads at any given time. In a forced air delivery system such as a forced air heating or cooling system, the amount of conditioned air available to a specific zone will often depend on the gross thermal capacity of the heating or cooling system, as well as the number of open zones at any given time.
In many forced air heating and cooling systems, each zone will have a damper that controls air flow to the particular zone. The zone damper can open to permit conditioned air to flow into the zone from a source of conditioned air. The amount of heating or cooling delivered to the zone is often a function of the thermal capacity of the conditioned air and the relative amount of time that the zone damper is open.
As noted, the actual amount of conditioned air (and thus the amount of heating or cooling delivered) can vary depending on, for example, the number of open zones or dampers relative to the total number of zones or dampers in the system. For example, as zone dampers close over time, more heating and/or cooling may be delivered through the remaining open dampers, sometimes resulting in significant variations in the amount of heating and/or cooling that is delivered to each remaining open zone. This variation in the amount of heating and/or cooling that is delivered to a zone can significantly degrade a controllers ability to maintain adequate temperature control within a zoned system. Thus, a need remains for methods and system for controlling forced air and/or other systems that can account for the status of other zones within a multi-zone system.